Pathophysiology of Evolution and Recurrence of Chronic Subdural Hematoma

Modified Burr-Hole Craniostomy for the Treatment of Chronic Subdural Hematoma in Adults

BACKGROUND

Burr-hole craniostomy (BHC) is considered to be the most effective method for the treatment of chronic subdural hematoma (CSDH), and middle meningeal artery embolization is a new therapy used in clinical practice in recent years to treat CSDH. However, the optimal therapeutic effect of these 2 procedures is still controversial. This study prospectively designed a modified burr-hole craniostomy (mBHC) with drainage to treat CSDH.

METHODS

A total of 101 patients diagnosed with CSDH from January 2019 to April 2020 were prospectively included in this study. They were divided into BHC and mBHC groups. Among them, 40 selected CSDH patients received mBHC treatment. For comparison, 61 CSDH patients who received BHC treatment were used as the control group. Primary outcomes were hematoma recurrence and postoperative complications. Secondary outcomes included midline recovery, hematoma clearance, operation time, and hospital stay. The Chi-square test was used to compare the 6-month follow-up results between the 2 groups.

RESULTS

Among patients treated with mBHC, 39 patients had a good prognosis, and one 87-year-old patient with bilateral hematoma died of postoperative heart failure. Of the patients treated with BHC, 52 patients had good prognoses, and one 53-year-old patient with unilateral hematoma died of postoperative acute intracranial bleeding. During the 6-month follow-up period, no relapse occurred in the patients treated with mBHC, whereas 8 (13%) of the patients treated with BHC relapsed. There was a significant difference in the recurrence rate between the 2 groups (P < 0.05). In addition, midline recovery, hematoma clearance rate, operation time, and complications were found to be significantly different statistically (P < 0.05), and other characteristics of operation and outcome were not significantly different (P > 0.05) between the 2 groups.

CONCLUSIONS

Modified burr-hole craniostomy has a positive therapeutic effect on patients with CSDH and is more effective than conventional BHC therapy.

Middle Meningeal Artery Embolization for Chronic Subdural Hematoma: A Multi-Center Experience of 154 Consecutive Embolizations

BACKGROUND

Middle meningeal artery (MMA) embolization has emerged as a promising treatment for chronic subdural hematoma (cSDH).

OBJECTIVE

To determine the safety and efficacy of MMA embolization.

METHODS

Consecutive patients who underwent MMA embolization for cSDH (primary treatment or recurrence after conventional surgery) at 15 centers were included. Clinical details and follow-up were collected prospectively. Primary clinical and radiographic outcomes were the proportion of patients requiring additional surgical treatment within 90 d after index treatment and proportion with > 50% cSDH thickness reduction on follow-up computed tomography imaging within 90 d. National Institute of Health Stroke Scale and modified Rankin Scale were also clinical outcomes.

RESULTS

A total of 138 patients were included (mean age: 69.8, 29% female). A total of 15 patients underwent bilateral interventions for 154 total embolizations (66.7% primary treatment). At presentation, 30.4% and 23.9% of patients were on antiplatelet and anticoagulation therapy, respectively. Median admission cSDH thickness was 14 mm. A total of 46.1% of embolizations were performed under general anesthesia, and 97.4% of procedures were successfully completed. A total of 70.2% of embolizations used particles, and 25.3% used liquid embolics with no significant outcome difference between embolization materials (P > .05). On last follow-up (mean 94.9 d), median cSDH thickness was 4 mm (71% median thickness reduction). A total of 70.8% of patients had >50% improvement on imaging (31.9% improved clinically), and 9 patients (6.5%) required further cSDH treatment. There were 16 complications with 9 (6.5%) because of continued hematoma expansion. Mortality rate was 4.4%, mostly unrelated to the index procedure but because of underlying comorbidities.

CONCLUSION

MMA embolization may provide a safe and efficacious minimally invasive alternative to conventional surgical techniques.

Bedside single burr hole craniostomy drainage of chronic subdural hematoma in the emergency room: A useful option in resource challenged settings

Background

In resource challenged environments, the standard treatment of chronic subdural hematoma (CSDH) in the theater may be delayed because of the endemic financial constraint and logistic problems with consequent negative impact on the outcome. An emergency bedside burr hole craniostomy with a local anesthetic at the accident and emergency ward may be lifesaving in patients presenting in extreme neurological conditions in these settings.

Case Description

We presented three patients (one male and two females) with CSDH who presented at our service in poor neurological condition. The patients were between 49 and 70 years. The Glasgow Coma Score ranged from 3 to 6. The three patients had respiratory and pupillary abnormalities at presentation. They all had bedside single frontal burr hole craniostomy drainage of the hematoma under local anesthesia at the accident and emergency unit of the hospital. Surgery was done within 1 h of review by the neurosurgical team in all cases. The duration of hospital stay ranged from 8 to 24 days. The outcome was good in all cases.

Conclusion

Bedside single burr hole craniostomy at the accident and emergency unit may be lifesaving in patients with CSDH who present in extreme neurological condition but in whom prompt standard surgical treatment in the theater is not feasible.

Arachnoid cyst in young soccer players complicated by chronic subdural hematoma: personal experience and review of the literature

Arachnoid cysts (ACs) are congenital intracranial benign cavities originating from the meninges during embryological development. Several studies have shown the existence of a relationship between AC and a higher risk to develop ipsilateral chronic subdural hematoma (CSH) especially in a young population. In the presence of an AC, the practice of sport activities may expose young patients to minor head trauma and to an increased risk of developing CSH. We describe three cases of young soccer players with AC associated with CSH. Then, we performed a literature review of all the reported cases in the literature of patients younger than 18 years with AC-associated CSH related to sport practice. A total of 33 cases, including the three cases reported by us, are analyzed. Soccer is the most represented sport activity in this association (39% of cases). The treatment of choice is surgical in all patients, with burr hole or craniotomy in similar proportions. In one-third of patients, the AC has been fenestrated. Outcome is good in all the reported cases. We reviewed the main pathogenic theories, the main surgical strategies described in literature, as well as recurrence rate of CSH, the association of AC and cranial deformities, and the clinical outcome. AC might be associated with skull deformities, but their real incidence remains unclear. The clinical detection of such anomalies should suggest performing further radiological investigations. If the presence of AC is confirmed, the practice of sport activities should not be avoided, as the real incidence of AC-associated CSH is not clear yet and the reported outcomes in literature are good. Surgical treatment of AC-associated CSH should be hematoma removal through burr hole, reserving AC fenestration only for cases with intracystic bleeding or recurrences. The surgeon should adequately advise and inform the young patients and their families that they could have an increased risk of developing CSH given by the presence of the AC, and that they should be referred to a neurosurgical center if they become symptomatic.

Understanding Subdural Collections in Pediatric Abusive Head Trauma

Life-threatening physical abuse of infants and toddlers is frequently correlated with head injuries. A common variant of the abusive head trauma is the shaken baby syndrome. The present review article sheds light on subdural collections in children with abusive head trauma and aims at providing a recent knowledge base for various medical disciplines involved in diagnostic procedures and legal proceedings. To this end, the different subdural collection entities are presented and illustrated. The pathophysiologic background is explained. Differential and age-diagnostic aspects are discussed and summarized by tabular and graphic overviews. Two problematic constellations frequently occurring during initial CT investigations are evaluated: A mixed-density subdural collection does not prove repeated trauma, and hypodense subdural collections are not synonymous with chronicity. The neuroradiologic analysis and assessment of subdural collections may decisively contribute to answering differential diagnostic and forensic questions. In addition to more reference data, a harmonization of terminology and methodology is urgently needed, especially with respect to age-diagnostic aspects.

Description of a Modified Technique (mini craniotomy-basal membranotomy) for Chronic Subdural Hematoma Surgery and Evaluation of the Contribution of Basal Membranotomy Performed as Part of This Technique to Cerebral Expansion

OBJECTIVE

To determine the effectiveness of basal membranotomy performed to ensure cerebral expansion in patients operated for chronic subdural hematoma.

METHODS

Patients who were operated for unilateral chronic subdural hematoma and underwent basal membranotomy in addition to hematoma drainage were included in the first phase of the study. After the superficial membranous structures were excised, the maximum perpendicular distance between the internal tabula and the cerebral surface was measured after subdural hematoma evacuation. Subsequently, basal membranotomy was performed, the maximum perpendicular distance between the internal tabula and the cerebral surface was measured again, and the improvement in cerebral expansion was statistically calculated. The improvement of cerebral expansion in the patients who had undergone double burr hole drainage was statistically calculated in the second stage of the study.

RESULTS

The cerebral expansion after the basal membrane excision was 41.1% in those with a 1.5- to 2-cm hematoma, 43.1% in those with a 2.1- to 3-cm hematoma, 43.5% in those with a 3.1- to 4-cm hematoma, and 45.4% in those with a hematoma thicker than 4 cm on average. No recurrence was seen during the 6-month follow-up in any patient. Double burr hole drainage revealed similar values for cerebral expansion increase with a mean value of 10%. The burr hole drainage was repeated because of recurrence in 5 patients during the 2-month follow-up.

CONCLUSIONS

The mini craniotomy-basal membranotomy technique provided statistically significantly better cerebral expansion in patients with chronic subdural hematoma when compared with the double burr hole drainage technique.

Pathophysiology and Nonsurgical Treatment of Chronic Subdural Hematoma: From Past to Present to Future

BACKGROUND

Chronic subdural hematoma (CSDH) is one of the more frequent pathologic entities in daily neurosurgical practice. Historically, CSDH was considered progressive recurrent bleeding with a traumatic cause. However, recent evidence has suggested a complex intertwined pathway of inflammation, angiogenesis, local coagulopathy, recurrent microbleeds, and exudates. The aim of the present review is to collect existing data on pathophysiology of CSDH to direct further research questions aiming to optimize treatment for the individual patient.

METHODS

We performed a thorough literature search in PubMed, Ovid, EMBASE, CINAHL, and Google scholar, focusing on any aspect of the pathophysiology and nonsurgical treatment of CSDH.

RESULTS

After a (minor) traumatic event, the dural border cell layer tears, which leads to the extravasation of cerebrospinal fluid and blood in the subdural space. A cascade of inflammation, impaired coagulation, fibrinolysis, and angiogenesis is set in motion. The most commonly used treatment is surgical drainage. However, because of the pathophysiologic mechanisms, the mortality and high morbidity associated with surgical drainage, drug therapy (dexamethasone, atorvastatin, tranexamic acid, or angiotensin-converting enzyme inhibitors) might be a beneficial alternative in many patients with CSDH.

CONCLUSIONS

Based on pathophysiologic mechanisms, animal experiments, and small patient studies, medical treatment may play a role in the treatment of CSDH. There is a lack of level I evidence in the nonsurgical treatment of CSDH. Therefore, randomized controlled trials, currently lacking, are needed to assess which treatment is most effective in each individual patient.

Middle Meningeal Artery Embolization for Chronic Subdural Hematoma

Purpose To evaluate the effect of middle meningeal artery (MMA) embolization on chronic subdural hematoma (CSDH) and compare the treatment outcomes of MMA embolization and conventional treatment. Materials and Methods All consecutive patients 20 years or older with CSDH were assessed for eligibility. CSDHs with a focal location, a thickness of 10 mm or less, no mass effect, or underlying conditions were excluded. Seventy-two prospectively enrolled patients with CSDH underwent MMA embolization (embolization group; as the sole treatment in 27 [37.5%] asymptomatic patients and with additional hematoma removal for symptom relief in 45 [62.5%] symptomatic patients). For comparison, 469 patients who underwent conventional treatment were included as a historical control group (conventional treatment group; close, nonsurgical follow-up in 67 [14.3%] and hematoma removal in 402 [85.7%] patients). Primary outcome was treatment failure defined as a composite of incomplete hematoma resolution (remaining or reaccumulated hematoma with thickness > 10 mm) or surgical rescue (hematoma removal for relief of symptoms that developed with continuous growth of initial or reaccumulated hematoma). Secondary outcomes included surgical rescue as a component of the primary outcome and treatment-related complication for safety measure. Six-month outcomes were compared between the study groups with logistic regression analysis. Results Spontaneous hematoma resolution was achieved in all of 27 asymptomatic patients undergoing embolization without direct hematoma removal. Hematoma reaccumulation occurred in one (2.2%) of 45 symptomatic patients receiving embolization with additional hematoma removal. Treatment failure rate in the embolization group was lower than in the conventional treatment group (one of 72 patients [1.4%] vs 129 of 469 patients [27.5%], respectively; adjusted odds ratio [OR], 0.056; 95% confidence interval [CI]: 0.011, 0.286; P = .001). Surgical rescue was less frequent in the embolization group (one of 72 patients [1.4%] vs 88 of 469 patients [18.8%]; adjusted OR, 0.094; 95% CI: 0.018, 0.488; P = .005). Treatment-related complication rate was not different between the two groups (0 of 72 patients vs 20 of 469 patients [4.3%]; adjusted OR, 0.145; 95% CI: 0.009, 2.469; P = .182). Conclusion MMA embolization has a positive therapeutic effect on CSDH and is more effective than conventional treatment. ^© RSNA, 2017.

Factors influencing the recurrence rate of operated chronic subdural hematomas

In this study we are trying to establish a correlation between the surgical technique used for the treatment of chronic subdural hematomas and the risk of recurrence. Between 01.06.2008 and 31.05.2014, 123 patients with 138 chronic subdural hematomas (CSDH) were operated on and followed-up in our department. Among them, 16 hematomas (11,6%) recurred. Factors related to the patients (gender, age, location of the hematoma) are analyzed as possible predictors of recurrence. Several surgical techniques were used in the treatment of chronic subdural hematomas. Each of them is analyzed to find possibly connections with the recurrence risk of the size of the approach, the reposition of the bone flap, the suture of the dura and other aspects. There are obvious, statistically significant correlations between the risk of recurrence and some elements of the surgical technique employed.

History of Chronic Subdural Hematoma

Trephination or trepanation is an intentional surgical procedure performed from the Stone Age. It looks like escaping a black evil from the head. This technique is still used for treatment of chronic subdural hematoma (SDH). Now, we know the origin, pathogenesis and natural history of this lesion. The author try to explore the history of trephination and modern discovery of chronic SDH. The author performed a detailed electronic search of PubMed. By the key word of chronic SDH, 2,593 articles were found without language restriction in May 2015. The author reviewed the fact and way, discovering the present knowledge on the chronic SDH. The first authentic report of chronic SDH was that of Wepfer in 1657. Chronic SDH was regarded as a stroke in 17th century. It was changed as an inflammatory disease in 19th century by Virchow, and became a traumatic lesion in 20th century. However, trauma is not necessary in many cases of chronic SDHs. The more important prerequisite is sufficient potential subdural space, degeneration of the brain. Modifying Virchow's description, chronic SDH is sometimes traumatic, but most often caused by severe degeneration of the brain. From Wepfer's first description, nearly 350 years passed to explore the origin, pathogenesis, and fate of chronic SDH. The nature of the black evil in the head of the Stone Age is uncovering by many authors riding the giant's shoulder. Chronic SDH should be categorized as a degenerative lesion instead of a traumatic lesion.

Usefulness of interventional embolization of the middle meningeal artery for recurrent chronic subdural hematoma: Five cases and a review of the literature

PURPOSE

Although several strategies against recurrent chronic subdural hematoma (CSDH) have been proposed, no consensus has been established. Recently, middle meningeal artery (MMA) embolization has been proposed as radical treatment for recurrent CSDH. We wanted to estimate the usefulness of MMA embolization for recurrent CSDH.

METHODS

From February 2012 to June 2013, 110 patients with CSDH underwent single burr-hole surgery with irrigation and drainage. Among these patients, 13 showed recurrent hematoma formation and were retreated surgically. Furthermore, repeated recurrence of CSDH was observed in six patients. Five of these six patients underwent middle meningeal artery (MMA) embolization with polyvinyl alcohol particles. All five patients with interventional treatment were observed for four to 60 weeks.

RESULTS

No more recurrence of CSDH was observed in any of the patients. During the follow-up period, no patients suffered from any side effects or complications from the interventional treatment.

CONCLUSION

MMA embolization with careful attention paid to the procedure might be a treatment of choice for recurrent CSDH.

Embolization of the Middle Meningeal Artery Effectively Treats Refractory Chronic Subdural Hematoma: A Systematic Review

Chronic subdural hematoma (CSDH) formation mechanism is very complex, and has not entirely understood. It represents a frequent type of intracranial hemorrhage, and is very common disease in Neurosurgery practice, especially in older patients. Various surgical treatments have been proposed for the treatment of CSDH. The rate of recurrence in CSDH after surgery ranges from 5% to 30%, repeated surgery must be considered. But in some cases subdural collections are still persistent. Endovascular embolization of the middle meningeal artery (MMA) is an option for treatment of refractory CSDH. We review all cases that were treated with embolization to assess the effect of this intervention. Our review revealed 6 papers with a total enrollment of 14 patients were treated with MMA embolization for refractory chronic subdural hematoma without any postoperative complication or recurrence. In this study we suggest MMA embolization as an alternative for treatment of non-curable CSDH, especially for old people with systematic diseases, who cannot tolerate repeat surgery.

Characterization of chronic subdural hematoma fluid proteome

BACKGROUND

Chronic subdural hematoma (CSDH) is commonly caused by head injury, but the progression of CSDH is recognized as an inflammatory process. The protein composition of the CSDH fluid has not been fully elucidated, nor has the contribution of its components to the enlargement of the hematoma cavity and to its chronic manifestation.

OBJECTIVE

To characterize the protein content of CSDH fluid and study the differences between CSDH fluid and serum to identify proteins putatively involved in the pathogenesis of CSDH.

METHODS

CSDH fluid and serum of 5 patients were investigated with 2-dimensional gel electrophoresis followed by glycosylation-specific fluorescence staining and mass spectrometry.

RESULTS

Two-dimensional gel electrophoresis revealed approximately 1100 protein spots in the CSDH fluid. We identified 213 spots representing 57 different proteins, most of which were glycosylated. The comparison with serum revealed 11 proteins with elevated levels in the CSDH fluid including carbonic anhydrase I, catalase, ferritin light chain, fibrinogen (α, β, γ), hemoglobin (α, β), malate dehydrogenase, peroxiredoxin 2, and transforming growth factor-β-induced protein ig-h3. The levels of haptoglobin and a fragment of complement C4 were decreased. Changes in spot positions were detected for apolipoprotein A1 and a fragment of complement C3.

CONCLUSION

The hematoma fluid originates mainly from blood and the results suggest the involvement of coagulation and fibrinolysis cascades. However, proteins with a potential role in CSDH pathogenesis were detected including carbonic anhydrase I, transforming growth factor-β-induced protein ig-h3, and the altered components of the complement system. Inflammation and fibrosis indicate targets for further studies in the pathogenesis of CSDH.

Refractory diabetes insipidus following drainage of chronic subdural haematoma

BACKGROUND

Post-traumatic diabetes insipidus (DI) is a relatively common complication after head injury. The authors report a fatal case of refractory DI, which developed in a patient with chronic subdural haematoma.

CASE HISTORY

A 38-year-old woman presented to the emergency room with a headache for over a week. She was alert and neurological examination demonstrated no significant deficits or external wounds in her head. Brain computed tomography (CT) scans revealed a small amount of chronic subdural haematoma bilaterally. She was treated conservatively and her hospital course was uneventful until she developed a convulsive seizure and mental change on the 3rd day after admission. Immediate follow-up CT scans showed no significant change in the amount of haemorrhage except effacement of gyral marking. Bilateral trephination and drainage of the haematoma were performed immediately. Post-operatively, she developed a refractory DI and was managed in the intensive care unit. However, she died on the 6th day after the operation ultimately.

CONCLUSION

The authors emphasize the importance of timely drainage of chronic subdural haematoma to prevent a fatal endocrinologic complication after head injury. This study also discusses the possible mechanism of DI after head injury, management and review of the pertinent literatures.

Postoperative course and recurrence of chronic subdural hematoma

OBJECTIVE

Chronic subdural hematoma (CSDH) is known to have a significant recurrence rate. There are different criteria defining the recurrence of CSDH. We evaluated the postoperative course of CSDH and tried to propose the reasonable criteria of recurrence.

METHODS

We retrospectively examined the medical records and pre- and postoperative CT scans of 149 consecutive patients who underwent surgery from January 2005 to December 2009. Diagnosis was confirmed by CT scanning or MRI. The postoperative courses were either resolved or recurrent. The resolved CSDH was one of the three types; early resolution, delayed resolution, or late resolution. The recurrent CSDH was one of the four types; recurrence without resolution, early recurrence after resolution, late recurrence after resolution, or recurrent-and-resolved type.

RESULTS

The CSDH was resolved within 30 days after surgery in 58 (39%) patients, between 1 to 3 months in 62 (42%), and after 3 months in 11 (7%) patients. The CSDH was recurred in 18 (12%) patients. Late resolution or recurrence was more common in the aged. The recurrent hematoma was seen on the same side in 11 patients, on the different side in 7 patients. Recurrence was significantly more common in the thick hematomas.

CONCLUSION

For a working criteria of the recurrence of CSDH, we propose the early recurrence as return of symptoms or reaccumulation of the hematoma after a surgery within 3 months regardless of the location, amount or repeated operations. The late recurrence can be defined as reappearance or enlargement of a liquefied hematoma within the cranial cavity surrounded by the membranes or persistent CSDH beyond 3 months after surgery.

Prolonged drainage reduces the recurrence of chronic subdural hematoma

Recurrence of chronic subdural hematoma (CSH) is a significant problem in neurosurgical practice. Various risk factors associated with patient's characteristics and the pathogenesis of CSH have been investigated in many studies, but controversial findings are not uncommon. Therefore we made a retrospectively investigation focusing mainly on the factors associated with surgical techniques. in order to find out the factors that may affect the recurrence rate of CSH. The medical records of 97 consecutive patients with 121 CSHs, who were treated with burr-hole craniostomy and continuous drainage, were retrospectively reviewed. The relationships between the recurrence rate and some factors associated with surgery, such as location of burr-hole, thickness of residual hematoma, location of drainage catheter, intracapsular air postsurgery, duration of drainage were investigated. The average recurrence rate was 6.6% in this whole series. For patients with less than three days of drainage, the recurrence rate was 16.3%, whereas for those with 3 and more days of drainage, the recurrence rate was only 1.3%. The duration of drainage significantly related to recurrence rate. In addition, a higher recurrence rate seemed to be associated with more intracapsular air postsurgery, but it did not reach statistically significant level in this study. Prolonged duration of drainage did not increase the frequency of infection in this series. We found in this study that the duration of drainage play an important role in the treatment of CSH and 3 full days of drainage seems to be necessary, especially for patients of 60 years and over. We presumed that it takes at least 3 days of drainage for outer membrane of CSH to get the restoration of a normal balance between coagulation and fibrinolysis after surgery, which is necessary for termination of the vicious cycle and resolution of the hematoma.

Influence of cranial morphology on the location of chronic subdural haematoma

BACKGROUND

The purpose of the present study was to evaluate the relationship between cranial morphology and location of a chronic subdural haematoma (CSDH) in patients with and without intracranial vault asymmetry.

METHOD

The study was conducted in 110 consecutive adult patients who underwent surgery for CSDH. The relationship between the following variables and CSDH was studied: sex, age, past medical history, history of trauma, interval between head injury and symptoms, clinical presentation, location of the CSDH, symmetry of the frontal and occipital intracranial vault on the CT scan and/or MR images, surgical treatment and outcome. Throughout the analysis, p < 0.05 was considered statistically significant.

FINDINGS

The frontal cranial vault was symmetrical in 48 patients (43.6%) and asymmetrical in 62 patients (56.4%). CSDH was more commonly bilateral in patients with a symmetrical frontal cranial vault than those with an asymmetrical shape (41.7% vs 17.7% and this difference is statistically significant (p = 0.01). In 62 patients with an asymmetric frontal skull vault, the CSDH was bilateral in 11 patients. In the remaining 51 patients, the CSDH was located on the same side of the most curved frontal convexity in 34 patients and on the side of the less curved frontal convexity in 17 patients. The occipital cranial vault was symmetrical in 44 patients (40%) and asymmetrical in 66 patients (60%). CSDH was more commonly bilateral in patients with a symmetrical occipital cranial vault than those with an asymmetrical one (40.9% vs 19.7%) and this difference was also statistically significant (p = 0.019). In 66 patients with an asymmetric occipital skull vault, the CSDH was bilateral in 13 patients. In the remaining 53 patients, the CSDH located on the same side of the most curved occipital convexity in 39 patients and on the side of the less curved occipital convexity in 14 patients.

CONCLUSIONS

Frontal and occipital intracranial vault morphology provides valuable information about location of CSDH. Bilateral CSDH is common in patients with symmetrical frontal and occipital cranial vault. In asymmetrical cranium, CSDH usually locates on the same side of the most curved frontal or occipital convexity. Identification of this relationship can be very useful to elucidate the origin and the pathogenesis of CSDH.

Chronic subdural hematomas : a comparative study of three types of operative procedures

OBJECTIVE

Several surgical procedures have been reported for the treatment of chronic subdural hematoma (CSDH). We compared the results of treatments for CSDH obtained from one burr-hole craniostomy with closed system drainage with or without irrigation, two burr-hole craniostomy with closed system drainage with irrigation, and small craniotomy with irrigation and closed-system drainage.

METHODS

Eighty-seven patients with CSDH underwent surgery at our institution from January 2004 to December 2008. Our patients were classified into three groups according to the operative procedure; group I, one burr-hole craniostomy with closed system drainage with or without irrigation (n = 25), group II, two burr-hole craniostomy with closed system drainage with irrigation (n = 32), and group III, small craniotomy with irrigation and closed-system drainage (n = 30).

RESULTS

Age distribution, male and female ratio, Markwalder's grade on admission and at the time of discharge, size of hematoma before and after surgery, duration of operation, Hounsfield unit of hematoma before and after surgery, duration of hospital treatment, complication rate, and revision rate were categories that we compared between groups. Duration of operation and hospitalization were only two categories which were different. But, when comparing burr hole craniostomy group (group I and group II) with small craniotomy group (group III), duration of post-operative hospital treatment, complication and recurrence rate were statistically lower in small craniotomy group, even though operation time was longer.

CONCLUSION

Such results indicate that small craniotomy with irrigation and closed-system drainage can be considered as one of the treatment options in patients with CSDH.

ReviewNatural history of chronic subdural haematoma

This review will clarify the natural history of chronic subdural haematoma (SDH). Chronic SDH has dual origins, one from subdural hygromas (SDG) and the other from acute SDHs. It occurs only in patients with a suitable pre-morbid condition, i.e. sufficient potential subdural space (PSS). In unresolved SDGs, proliferation of dural border cells produces the neomembrane. Unresolved SDGs become chronic SDHs by repeated micro-haemorrhages from fragile new vessels, which were grown into the neomembrane. When PSS is sufficient, acute SDHs may become chronic SDHs. Chronic SDHs enlarge when rebleeding exceeds absorption and they become symptomatic. When the neomembrane is matured, the neocapillary is no longer fragile. If absorption exceeds rebleeding, the haematoma will disappear. Maturation of the neomembrane and stabilization of the neovasculature eventually result in spontaneous resolution. The fate of chronic SDH depends on the pre-morbid status, the dynamics of absorption-expansion and maturation of the neomembrane.

Management and outcome of patients with acute traumatic subdural hematomas and pre-injury oral anticoagulation therapy

BACKGROUND

Acute subdural hematomas (aSDHs) are found in up to one-third of patients with severe traumatic brain injury and are associated with an unfavorable outcome in the majority of cases. Mortality ranges between 40 and 60%, but was reported to be even higher in patients undergoing oral anticoagulation therapy (OAT) at the time of injury. The objective of this study is to specifically report on the peri-operative management and outcome of patients with aSDH and pre-injury OAT.

MATERIAL AND METHODS

From June 2002 to June 2006, all patients with OAT who underwent surgical treatment of aSDH were retrospectively analysed. Results of pre-operative blood tests, the peri-operative and surgical management and the clinical courses were assessed. Patient outcome is reported according to the Glasgow Outcome Scale (GOS) at 6 months.

RESULTS

Eleven (10.3%) out of 107 patients with aSDH were on OAT. Patients with OAT were significantly older than patients without OAT (72.4 +/- 9.3 versus 59.9 +/- 17.5 years; p<0.05, Mann-Whitney U-test). Intensity of head trauma was moderate in four and severe in seven patients with a median pre-operative Glasgow Coma Scale (GCS) of 8. Median pre-treatment prothrombin time and international normalized ratio were 23% (range: 10-65%) and 3.3 (range: 1.5-10.6), respectively. Replacement therapy consisted of administration of prothrombin complex concentrates, vitamin K and FFP (fresh frozen plasma). In four patients, antithrombin was additionally given to prevent disseminated intravascular coagulation. Surgical treatment consisted of craniotomy (n=10) or craniectomy (n=1) and hematoma evacuation with intracranial pressure probe placement. Low molecular weight heparin was administered as pharmacological prophylaxis of thrombembolic events in an increasing dose post-operatively. At 6 months, six out of 11 patients survived with a median GOS of 4. All-cause mortality was 45.5%. A pre-operative GCS of < or = 8 was not associated with an increased risk of mortality (p>0.5, Fisher's exact test). No relevant rebleedings or thrombembolic complications were observed. The mortality rate of patients who did not undergo OAT was 50%.

CONCLUSION

A large number of patients with aSDH are on pre-injury OAT. Specific replacement therapy facilitates successful clot evacuation without bleeding complications. The overall outcome of these patients does not seem to differ from historical cohorts with aSDH without OAT, but a large prospective multicenter study is warranted to answer that question.

Morphological aspects of the traumatic chronic subdural hematoma capsule: SEM studies

The morphology of the outer and inner membranes of traumatic chronic subdural hematomas (CSDHs) surgically removed from eight patients was investigated by scanning electron microscopy (SEM). Hematomas were divided into three groups based on time that had passed from the initiation of trauma to surgery. Structure of the CSDHs showed gradual morphological changes of the developing hematoma capsule. They initially included angiogenic and aseptic inflammatory reactions followed by progressive involvement of fibroblasts-proliferating and producing collagen fibrils. Numerous capillaries suggesting formation of new blood vessels were observed mainly in young hematomas removed between 15 and 21 days after trauma. In "older" hematomas (40 days after trauma), more numerous capillaries and thin-walled sinusoids were accompanied by patent, larger diameter blood vessels. Within the fibrotic outer membrane of the "oldest" hematoma capsules (60 or more days after trauma), especially in the area over the hematoma cavity, blood vessels were frequently occluded by clots. The results suggest dynamic changes in cellular and vascular organization of traumatic CSDH capsules paralleling the progression in hematoma age.

Growing skull fracture in the absence of a dural tear

A case of growing skull fracture associated with unrecognized extradural haematoma is presented together with the relevant radiology. The pathophysiology of growing skull fracture is reviewed in light of this previously unreported case.

[Chronic subdural hematoma: study of 161 patients and the relationship with coagulation abnormalities]

The chronic subdural hematoma represents one of the most frequent types of intracranial hemorrhage. One hundred sixty one patients operated in the Clinical Hospital of State University of Campinas-SP (UNICAMP) from April 1994 to May 2000, were analyzed retrospectively in order to characterize the population and to study the importance of the pre-operative coagulation analysis in the outcome. The majority of the population was male (86%), white (85.1%) and in the fifth decade (median age: 57 years). A high mortality index in the postoperative period was found in patients with INR (international normalized ratio) values greater than 1.25 and/or thrombocytopenia (p<0.001 and p=0.004 respectively). Patients with previous head injury history (76%) showed a lower mortality (p=0.044). The results stand out the importance of the pre-operative evaluation with coagulation studies in order to correct possible abnormalities.

Coagulopathy and outcome in patients with chronic subdural haematoma

OBJECTIVE

The coincidence of coagulatopathy and chronic subdural haematoma (CSH) requires correction of coagulation to facilitate surgery. We investigated the correlation between coagulopathy and outcome in CSH patients.

MATERIAL AND METHODS

We analysed past medical history, surgical treatment and coagulation parameters of 114 patients.

RESULTS

Coagulation disorders were found in 42%. Preoperative treatment with prothrombin complex concentrate was necessary in 14%. A significant difference (P < 0.05) of the preoperative level of platelets was found between recurrent CSH and non-recurrent group. Totally, we had to perform re-operations in 17.5%. Eighty-one patients presented with Glasgow coma scale (GCS) > or = 13. After surgery GCS was > or = 13 in n = 92. There was an improvement of GCS in 46 cases, 61 patients maintained GCS score levels. Outcome was significantly worse in the alcoholic group (P < 0.001), and in the recurrent group (P < 0.05). In patients with substitution of coagulation factors, outcome was worse in the group with post-operative substitution only (P < 0.05).

CONCLUSION

In CSH, the coagulation parameters and a subtle correction of coagulation are of special interest, regarding the worse outcome in patients with recurrent CSH and in those requiring post-operative substitution.